Concept : Average Demand The average of loads occurring on the power station in a given period (day or month or year) is known as average load or average demand Maximum Demand It is the greatest demand of load on the Power Station during a giving period is known as Maximum Demand. Demand Factor It is the Ratio of Maximum Demand on the Power Station to its Connected Load. The value of Demand factor is usually less than 1. It is excepted because maximum demand on the power station generally less than the connected load. Plant Capacity Factor The Plant Capacity Factor is the ratio of average demand on the Power Station divided by the maximum installed capacity of the power station. Plant Use Factor: It is the ratio of kWh generated to the product of plant capacity and the number of hours for which the plant was in operation. Diversity Factor The Ratio of the sum of individual maximum demands to the maximum demands on power station is known as Diversity Factor Load Factor The Ratio of Average Load to the Maximum Demand during a given period is known as load factor. Plant Load Factor The Plant Load Factor is defined as the ratio of the output of power station in kWh to the rated capacity of the plant. Calculations : Given Max Demand = 100 kW p.f = 0.8 lagging Load Factor = 60 % The tariff used is Rs. 75 per kVA per annum of maximum demand plus 15 paise per kWh consumed. No of Units Consumed = Load Factor × Max Demand × 8760 = 0.6 × 100 × 8760 = 525600 units kVA = kW / pf = 100 / 0.8 = 125 kVA Tariff = (125 × Rs 75.00) + (525600 × Rs 0.15) = Rs 88215